Alfeed nobel



(No Model.)

A. NOBEL. Primer for Blasting Charges.

Patented Aug 17,1880.

INVENTOB 72m WITNESSES: 0 L/ W ATTORNEYS.

' UNITED STATES PATENT OFFICE.

ALFRED NOBEL, 0F PARIS, FRANCE.

PRIMER FOR BLASTlNG-CHARGES.

SPECIFICATION forming part of Letters Patent No. 231,348, dated August1'7, 1880.

Application filed April 7, 1880.

a and b are two hollow cylinders of compressed granulated gunpowder withtheir hollow space 0 filled with dynamite or analogous fulminate orexplosive. The two cylinders a and b are glued together on the line d'e. A fuse, f, is fitted into the hole It, and a paper wrapped aroundthe primer is secured to the fuse with a string.

An exploder of this kind fired in a bore-hole on the top of a charge ofmeale(l'compresse(l powder readily sets on the latter. A very suitableprimer can also be made by mixing together about equal parts ofgunpowder in fine grains and picrate of potash, or bibasic picrnte ofbaryta, or tribasic picrate of lead. They may either be mixed looselyand filled into a small paper cartridge, or be compressed into smallcakes of the weight of eight to ten grams each. Such a cake, along withthe end of a fuse, is wrapped into apaper, which is secured to thefusewith a string. A primer of this kind, especially if pieiate of potash isthe vivifying medium, is but slightly sensible to concussion.

The cylinders of inealed gunpowder above referred to should be veryhighly compressed, so as to obtain great density. The machinery used forcompressing gunpowder is too well known to require special descriptionhere. In the above-described mealed compressed gun- (No model.) Patentedin England June 17, 1879.

powder nitrate of soda or nitrate of baryta, 5

especially the former, may be advantageously substituted for nitrate ofpotash.

A bore-hole is chargedas follows: As many cylinders of compressed mealedpowder as needed are put in and pushed home. Over these aprimer-cartridge, as hereinbefore described, is introduced. The hole isthen tamped and the charge fired.

In very soft and fissured ground it is better to make use of a violentfulminate, such as dynamite, instead of the somewhat" slower picratesabove referred to.

. In the above description I have only alluded, generally, to ordinarymealed gunpowder without specifying its ingredients but I wish it to beunderstood that Imay use any analogous composition possessing the sameproperty of onl fusin and not ex lodin when compressed in a mealed'condition and charge into a borehole in that shape.

I also remark that although the compressed mealed gunpowder hereinspecified constitutes no new composition of matter, yet it becomespractically a new material, or acquires a new property by addition ofthe i'ulminate, viz., that of being explosive under conditions where itotherwise would only fuse.

Having thus described my invention, I claim as new and desire to secureby Letters Patent- A primer for mealed powder, consisting of the twocylinders a b, glued together on the line (1 0, containing a centralfilling of dynamite surrounded by granulated powder and provided with afuse, f, passing through the hole h, as shown and described. I Intestimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

. ALFRED NOBEL.

Witnesses: l

FRANZ HASSLAGHER, JOSEPH PATRICK..-

